Process of making splints



oct. 2.1,- 195s l A. E. MURRAY PRocEss oF MAKING SPLINTS 4 Sheets-Sheet 1 'Filed Feb. s. 1954 lrllla m Tr www .E nm

ATTORNEY vOct. 21, 1958 -A. |v:. MURRAY 2,856,919

PROCESS oF MAKING SPLINTS v Filed Feb. s, 1954 4 sheets-sheet 2 INVENTOR .lcrn E Marra Oct. 21, 1958 A. E; MURRAY 2,856,919.

PROCESS OF MAKING SPLINTS Filed Feb. 3, 1954 4 Sheets-Sheet 3 o 9 g0voofoo`oo VINVEN'roR Elan Oct. 21, 1958` v A,.E, MURRAY 2,856,919

PROCESS OF MAKINGSPLINTS r v Filed Feb. s, m54 'l v 4 sheets-sheet 4 lanYJE. Maffay I OR Y nited States jatent PROCESS F MAKING SPLINTS Alan E. Murray, New York, N. Y.

l Application February 3, 1954, Serial No. 407,857

4 claims. (Cl. 12s-90) My invention relates particularly to splints which may be. applied over any desired portions of the body, such for instance as the arm, leg, neck, etc., to facilitate and correct the healing thereof, especially in the case where there are broken bones present, which require to be knitted together in the correct position.

An object of my invention is to provide more elfective splints than were hitherto available, so as to eliminate the dangers that have occurred in the utilization of hard plaster of Paris splints of the usual type.

It has been found in practice that the usual plaster ofParis splints set very quickly and unevenly into a hard mass, which ofttimes has resulted in undue constriction ofthe arm or leg so that when left on the member.

until the healing has been completed alack of circulation has resulted due to the uneven and unnatural binding by the plaster of Paris splint. In fact, malformations of the arm or leg have occurred therefrom which could not be thereafter corrected, so that the patient has at times been required to go through the remainder of his life with the resultant deformities.

It is one of the objects of my invention to avoid such disadvantages and dangers by providing splints involving the use of plastics, such for example as latex, etc.

As the latex herein referred to, I preferably use a latex which is a water-suspension of self-vulcanizing articial rubber known as .neoprene, although latex made of natural rubber or any artificial rubber can be used herein. For the thickened latex herein I may use the thickened latex such as referred to in my Patent No. 2,568,291, which is made, as stated therein, by adding a thickener, such as methyl cellulose, to the self-vulcanizing watersuspended neoprene latex generally sold under the same name latex.

The splints made in accordance with my invention are controllable over the entire area of the body portion, or

member, under treatment and they permit the development, furthermore, of the dynamic natural position of the member throughout the treatment, by interpreting the position given to the arm or leg initially by the orthopedist in terms of the hydraulic technique demanded by the soft tissues which enclose the bones while being knitted or otherwise treated. In other words, although the member during treatment may be immobilized, nevertheless the splints made in accordance with my invention are much softer than any previous splints and more hydraulic in operation, and of such a character, furthermore, as to be capable of frequent replacement and such as not to set merely in spots before complete healing has taken place.

Further objects of my invention will appear from the detailed description of the same hereinafter.

While my invention is capable of embodiment in many diierent forms, for the purpose of illustration I have described and shown in the accompanying drawings only certain embodiments thereof, in which- L Fig., .1 shows a plan. View of a patient inza reclining man Patented Oct. 21, 195,8

" icc invention, as applied to the right arm;

Fig. 2 is a cross-section of the said arm, showing applied thereto windings of felt and outside of the latter' windings of monks cloth;

Fig. 3 is a cross-section of the said arm showing the upper half of the said windings of felt and monks cloth removed and substituted with an upper half of a plaster of Paris negative over the said arm with supporting loops of string embedded therein;

Fig. 4 is an elevation showing the said upper half of plaster of Paris having the same supported from a neckencircling strap; p

Fig. 5 is a vertical section of a wall against which the patient is leaning his head and upper half of the plaster of Paris negative illustrated in Figs. 3 and 4;

Fig. 6 is a cross-section of the said arm showing as applied thereto both the upper and lower halves of the plaster of Paris negative which form together a negative cast;

Fig. 7 is a plan view of a positive master cast of plaster of Paris made in the said negative of Fig. 6;

Fig. 8 is a cross-section through the said masterv cast of Fig. 7, having applied thereon two halvesv of monks cloth asover-laid and enclosed withcelastic;

Fig. 9 is a plan View of the resulting two halves of the splintcomprised of monks cloth and celastic bound together at the joints of the two halves by lacings;

Fig. 10 is a side elevation View of a detail of the splint shown in Fig. 9, but having a different mode of attachment of the two halves together, instead of by the lacings;

- Fig. 11 is a cross-section of the positive plaster cast of the arm showing thereon the application of an alternativej form of splint instead of the celastic splint shown in' Figs. 8 and 9;

- Fig. 12 is a plan view of the splint shown in Fig. 11,- having applied to the outside thereof longitudinal strengthening strips and transverse loops for attaching the halves' thereof together with cotter pins, as well as supporting straps with eyelets therein; f

Fig. 13 is a plan view of a soft mobile splint made in the making of a nal splint of the entire leg and foot;-

Fig. 17 is a front elevation of the splint being made for the neck of a patient; and

Fig. 18 is a transverse section showing a modified mobile splint.

In carrying out my invention, it will be assumed that there is a broken right arm 1 to be set, and yhealed with the aid of the splints made in accordance with my invention.A As soon as possible after the breakage has occurred the orthopedist will set the position of the broken bonesin the natural location of the bones before breakage. Thereupon, I provide a number of strips of felt 2, about 1A" thick, obtained preferably as a split from felt 1/2,thick. The split of the desired thickness is easily pulled olf, but preferably in a tangential direction to the roll of felt, in the form in which it is produced on the market. The 1A Athick felt thus obtained is found to be very soft and resembles in texture a series of layers of wool flock. These strips are preferably rnade strip ,is applied ,tothe'; armit is laid-flaton aisupportY ofanyrkind, and fpowdered over' the,A inner, and outer snrfaces thereofwth powdered plaster ofvP-aris.

The winding of each strip, thus prepareiiiseompleted as `quickly ,as possible so -as Ato surround lthepentire arm, or` .at least the portion containing the :broken "bone, :and the windings are thus built up into a crudezthick -wall made-fromtthe Ysoft,fpieeestof feltandv preferably so as totipake the twall thicker over the `elbow or-wherever desired to obtain additional strengthening by ;the :felt. The Aimpregnated ;fe1 t, -with :or without `the dusting of plaster rit-Paris, begins to contract immediately even while putting .,itgon, the arm, dueto kthe gelling of the latex. The felt itself is found to accelerate the gelling due to thepI-I `characterof the felt but it is found, also, ithat the plaster OParis, if used,'furtherV facilitates andi-accel-` eratesthegelling of the latex, which-,takes place by an evencontraction all over the arm. This raction is ffar superior to what occurs-in theusnal plasterrof lParis cast madelwith cheeSecIOth, which becomesfrockflike'almost immediately, and which in practice .is-foundyto be un-y evenly hard in different spots, which quick uneven setting tof ythe plaster impels the orthopedist generally unduly-tand incorrectly tornanipulate the bonepositions. Onthecontrary, ,in the splints thus :made in;accordance Withmy invention, the splints are'yieldingand subject tonatural shaping under the influence ofthe soft tissues, so thatthe arm, or other portion ofthe body,';has an opportunity to assume naturally the physiological contonrsfduegto the fhydrauliccharacter ofk the'tissues enclosed, In otheriwords, thereconstructive powersi of'v the bodyareutilizedto the maximum extent sothatthe'arm acguiresnthe natural conformation demandedby thebody tissues.

i 1I then apply to the outside Yof the felt, :all over the 815111,.. Some of the latex, followed Ibytpowderedtfplaster of Paris. Next, I wind around, all o ver the felt, .strips offnonkis cloth 2o of the same dimensionsas the felt strips v2, in order to seal the latex while wet within the felt. At the same time, or right after applying the monks c1oth-;strips.2a, I apply tothe inner sideofV the .monks cloth 2a, while on'the arm,.a1monks clothstrap 3 .which hasgbeen impregnated withy latex, and dusted withl plaster of; Paris as in .the case of the other monks cloth 2o, which can lbe cut through .by asplit 4, thus producing two straps ,Standf which are provided with pairs-ofeye lets 7 and 8, as shown in Fig. 2.

Anaelectricl-pad, or current of warm air from anrelectric hair-dryer fan, is then applied, at intervals, to `the enclosing :layersof felt 2 Iand monks cloth 2a until ethe same are dry, twhich usually requires a period of about two days. vThis heating effect avoids lowering the patients temperature due tothe evaporation ofthe latex, which might otherwise ytend to give the patient a cold,

and has anadvantageof'lesseningV the pain of the healingr.

Thereupon, a-fter about-three days following .the apply.

ing of the, felt vZand monks cloth '2a. to the arm, twoy patientismade tolie down on -his.side, preferably, :while an upper half 11 of the enclosure, comprised ofV layers;

2 and 2a, is removed, thus leaving a lower half 12 resting on the body, supporting therein the arrn. Then, I apply all around the upper edge of the lower enclosure 12 a flange 13 of plastelene, about 3A wide, which is a molding clay comprised of clay intermixed with a fatty or greasy material to prevent the clay from setting too soon. This is accomplished by squeezing the plastelene from a collapsible tube containing the same so as to make the ange v1? extend outwardly onthe inner and outer faces of the arm throughout the length of the lower enclosure 12.

Then, I prepare a basin of ,plaster of Paris andtcool water'to a thick creamy consistency, having therein about a teaspoon full of salt' to a l2" diameter basin 31/2 deep, approximately lled with the said creamy plaster of Paris mixture. With a spoon or a spatula I now flow this plaster of Paris cream all over the upper face of the arm-,so .asttoform a thicknegativeplaster cast,:14:,ex tending'upwardly :from the said' ange y13 on each ;side of -,thev arm, as'shown in Fig. 3. -Before the;plaster of Paris upper cast llkhardens I embedtherein arpairfof string loops 1S andr16. This plastersets, ingaboutrve minutes, into a hard rocklike-mass, andlthenlintroduce` through-vthetloops 15 and.16,;as shown inFig. 4,-a:.neck

encircling strap 17 having the `usual buckle =18.fso that the -said strap 17 .extends tautly, but not tightly, up ,and

around the neck ofthe patient.

Now, the patient,as shown in Eig. 5, is madestofstand, or-sit up, sothat-his head and upper half of the mega;- tive Iplastercast ,1,4 restagainsta wall.19. Thereupon,

l `takeoff the lower half '12 of-thefelt andfmonicsaeloth enclosure ,and tear olf the plastelene strips. .It willihe found that vthe upper, half` 14 of thezplaster cast .will now. support athe-.arm:etlectively, .by means of Athe -strap 117 by adhesion, etc. thefplaster cast -14 are now coated .with a .solutiontof Sodiumilicaeof any desiredaconsistency, thatjs-tofsay` Next, I applyto; .thevunder portiorrof soluble glass. arm, inj :the place of the -removed lower enclosure 12, a liquidrcomprised ofrplaster :of Paris and water:.20`f,.o1i butter-likedensity, against the silicate rof soda ledges of theupper `plaster cast 14. Thisfplaster sets infabout tive lminutes and thev patientis then made to resumen reclining position. Now, the lplaster is Atapped lightly alongthelongitudinal,-meetingedges of :the twornegatives 14and 2,0with a mallet or small hammer vandythe itwn halves .arey separated, with the aid .of a table eknif'eizto loosenthegjoints.

The top half 14 of the plaster negative cast is; now removed after taking thefstrap 17 out of the loops .'15` and 16, the lower half 20 being now supporterlxbyV :the body ofthe patient. Clean the exposed upper `side vof the arm with a little rubbing alcohol. Next, put vonto theupper side ofthe larm the topthalf y1l of the softifelt andV monks -cloth splint, restingv the edges ,thereofagainst thelowerplaster half 20 ofthenegative cast.

Again, thepatient stands up and leansagainstthexwall- 19, as ,in Fig. 5. A string is 'then placed through the eyelets 7 land throughthe strap V17. Thenthe lower ,half 20 of the plaster cast negative is taken off and the ylower soft splint 1.2 is slipped Vonto the underside lof the arm, and adhesive tape is now wound around the felt .negativesplint with about six windings or more on every portion of lthe arm, to hold the, two-halves together. lThen the same string 'is passed; also, through the eyelets 8 andfthrough-the strap '1"7. Strong' elastic rubber "bands are-now placed'over the'two halves to keep them together before making the positiveplaster cast. l p

'Tofcomplete a negative cast-the two plaster halves 14 and 20 are now'placedI together, with their edges ''tting together, after applying a silicate of sodium solution theretoon their inner faces, throughout the interior' of thesnegativecast; l

This provides a negative master-cast yof plaster-from which Aespositive cast: can' lbe matlefbyf closing Aotfnhe Thelower edges gofwthe upper half of this leaves a plaster of Paris positive 22, from which to make any number of desired splints having the true conformation, with the correct reproduction of the shape of the physiological arm, in the correct position of choice determined by the orthopedist, and which may be light and elastic. This light perfected splint 23, in two halves 24 and 25, can be made by putting on the positive cast 22 a top L-shaped monks cloth 26, after coating the cast 22 with some of the thickened latex while turning up at the inner and outer sides of the arm 1/2 side anges 27 and 28 all around the parting lines, corre-v sponding in position to the lines 9 and 10. Then turn the cast over 22 and put a second piece of monks cloth 29,0ver the remaining side of the cast 22 with flanges 30 and 31 thereon,` proceeding as in the case of the monks cloth 26. Y

Then, after placing the cast 22 in the original position I provide a sheet of celastic material 32. This material is a heterogeneous mixture of nitrocellulose, that is to say pyroxylin and camphor, carried in a sheet of loose Weave cotton pile fabric, although the camphor may be omitted. It has the appearance of blotting paper before having the solvent applied thereto. The celastic material is applied (using rubber gloves, preferably) by iirst softening it in a liquid solvent which is non-watermiscible ketone or ester such as methyl ethyl ketone or ethyl acetate or a mixture of solvents such as methyl alcohol and ether, so that when the solvent liquid evaporates there is left an elastic form-retaining shellv similar to Celluloid. Any other elastic plastic material which can be softened by solvents leaving a stiff hard form-retaining shell by the evaporation or elimination of the solvent liquid, could be used. The sheet of softened celastic material 32 is worked in with the lingers over the monks cloth 26, providing flanges 33 and 34 thereon, as shown 'in Fig. 8. Then turn the cast 22 over and apply thereon, similarly, a celastic sheet 35 with flanges'36 and 37. Now, after cutting the two halves 32 and 35 apart with a razor between the flanges longitudinally on the inner and outer sides of the cast 22, holes 38 can be made through all these anges, as in Fig. 9, and lacings 39 and 40 can be passed through the holesto bind the two celastic halves 32 and 35 together, when placed on the arm of the patient during convalescence.

As an alternative form of fastening, however, I may, as shown in Fig. 10, cut oif all the said flanges shown in Fig. 8 and while the celastic 32 and 35 is still soft from the presence of the solvent, I can apply to thecelastic margins 32 and 35, respectively, on the inner and outer faces of the arm cast 22, a series of celastic strip loops 41 and 42, which have looped ends passed over a series of cotter pins 43 that can be removed and replaced when removing the hard dry celastic shell 32, 35 from the positive cast 22 and then applying the celastic shell to the arm of the patient during convalescence. Perforated supporting straps 43a, of celastic, over any selected loops 41 andy 43, may be similarly applied to the upper and lower celastic halves 32 and 35;

This technique, thus, provides rst the two felt halves 11 and 12 as a positioner and thereafter a top or first plaster half 14 of the negative cast which acts as a bacle, while the lower half 20 of the plaster negative applies the correct physiological shape Vof the arm hydraulically against the baffle 14 in the process of forming the splint., The felt positioner 11, 12 provides the correct position and the plaster preserves the1 correct hydraulick conformation of the tissues of the bodyY meminner and outer sides of the' cast 22.

ber, without the distortion previously produced Vby the uncontrollable, uneven, quick rock-like hardening of the usual plaster splints, for making final rigid or elastic or semi-flexible or soft splints therefrom. An alternativemode of procedure in making the nal splint, and especially where it is desired to provide a f softer and more flexible nal splint, vto be used instead of the celastic splint of Figs. 8 and 9, is shown in Figs. 1l and l2. In accordance with this procedure, I apply `latex all over the positive cast 22. Then I provide a i sheet of felt 44, about 44,2" thick, similar in character to that above referred to, having in general the L-shape of the upper face of the positive cast 22 so as to be wide enough to cover the entire upper or outside half of the cast 22 and so as to produce horizontal flanges 45 and 46 all around the inner and outer meeting edges of this. felt 44, adjacent to a similar lower felt 47 to be applied.,

later to the underside of the arm, with like anges 48 and 49. Before being applied over the cast 22, the upper felt 44 is powdered on 4the inner face with plaster of Paris and the upper or outside side of the said` felt 44 is then coated with Duco cement, which is acellulose acetate dissolved in any suitable volatile solvent. This cement may be applied to the outer face of the felt 44 before or after being applied to the positive cast 22.v

Two other pieces of felt of the same character, shape and size 50 and 51 are then each coated on the outside with Duco cement in the same manner and successively applied over the top of the felt layer 44. Then, in a similar manner, three similar layers of felt 47, 52 and 53 are applied to the underside of the arm with similar anges in each of the six layers, each of the said felts y 44, 50, 51, 47, 52 and 53 being provided with flanges,l

as above referred to, around the vmeeting edges on the If desired, there can be applied a fourth felt layer 55, to decrease thermoconductivity, in two halves and in the same manner respectively above and below the cast 22. Also, if de-f sired, there may be applied upper longitudinal reinforcing strips of felt 56 and 57 in a similar manner to the truding flanges of the felt layers `on the inside of the v cast as well as the outer side thereof. Any number of short fastening straps 60 may be applied to the inner and outside edges of the upper half thereof, each of which is provided with a loop 61 protruding over the meeting edge of the lower half thereof, and similarly looped straps 62 may be applied over the lower half.- All of these straps are fastened to the adjacent felt layers 51 and 53 or the felt layers 54 and 55 with the sa`rne technique as used in applying the succession-of felt layers to the cast 22. However, it will be noted that the loops 61 are placed so as to be laterally adjacent to the loops 62 so as to permit the insertion of cotter pins 63 in the adjoining loops 61 and 62 alon the inner meeting edges of the two halves. t

Instead of these last mentioned splints shown in Figs.

11 and 12, which are also somewhat rigid, in a way simi-k lar to the splints of Figs. 8 and 9, I may provide a mobile splint, to be used during the nal convalescence of the patient, as shown for instance in Fig. 13. This is a semi-elastic splint which can have varying degrees of4 elasticity, according to its thickness etc., which is particularly useful in the final healing of the member where some portions of the splints may be located 4opposite to bone ends that are chafed or sore, due to the thinness` chafed or sore portion of the body, thus producing a modified positive `cast 65. On this cast 65 the elastic splint may-then be madefrom 1/32'"thick felt66, in the same manner as 'described in connection with Figs. 1l and l'2"but by using, in this instance, the thickened form of latex on the felt 66, but with the same technique as just describedpreviously. Thereupon, I applyabove and below 'the cast 65onthe upper and lowerfelts 66 thicker L''shaped pieces 'of felt-67, about 1A" thick, which can be of a cheaper grade of'felt, which is usuallyl dark grey. For applying the pieces-of felt67 above and below the cast, the said layers V67 are first dipped in latex and wmng out to remove the excess of the latex. Also, beforethese'layers 67are appliedthe thinner felt layers 66 are brushed with thickened latex. Before applying the layers 67, furthermore, the latter'may be powdered on r'the inner faces lwith plaster -of Paris just after being dipped in the latexv andwrung'out. They are then immediately Apressed down onto vthe thin felt layers 66. It will be understood that .these layers 66 and 67 are all provided with theiianged edges in applying the same over the positive cast atthe lines Where the upperand lower halves of the'felts meet along the inne-rand outer faces of the cast 65,

Then, longitudinal reinforcing strips 68 and 69 may be applied to the top and bottom felts67, as in thecase of the felt laminations coated with the saidDuco cement. Perforations 70 can be made at intervals, in theV strips 68.and 69 and through the layers 66 and 67, after cutting off the inner and outeriianges on said felts and severing the two splint halves, along the inner and outer sides of the splint, with a razor blade, and removing them from the positive cast 65. However, instead of the thick felts 67 there may be applied pieces of celastic /g thick, with the aid of the solvent technique previously .described, which may be fastened together as shown in Figs. 9 or l0.

It will be understood that any of the reinforcing strips 56, 57, 68 and 69 can be omitted, if desired, to make the splint more flexible. Also, in this construction, instead of using Cotter pins for fastening the-edges together, as shown in Fig, 10, I can fasten the meeting edges ofthe two splint halves by having-near each of the fouredges shoe-eyelet hooks 71 and short rubber bands 72 thereon, to -be stretched onto the opposing shoe-eyelet hooks 71 to releasably fasten the same together. This enableszthe tightness of the splint to be readily controlled by selectingrubber bands 72 of the desired length and thickness, and which may be very thinduring final convalescence. The avoidance Aof pressure can be aided by-eliminating some of the rubber bands .72 vwhen desired. This, fur-` thermore, permits and preserves the dynamic use of the arm by partially opening the joints of the splints during convalescence, =to improve the circulation of the blood andbring about better Contact of the skin with the air, thus facilitating the healing action.

If it happens that the arm `or other member of the body shrinks while healing, so that the splint becomes too loose, this can be offset to the desired extent by applying to the inner faces of the splint halves one or more layers of terry cloth 73 and 74 having Duco applied to the outer faces thereof, as indicated by dotted lines in Fig. ll.

As above indicated, any other members orparts of the body can be provided 'with splints in substantially the same manner.

For example, as shown in Fig. l5, if a leg 75 has been broken and is to be provided with a splint, this can be done in any ofthe ways hereinabove described', as for instance involving thev making of initial wrappings 76 o'f felt and monks cloth, which may be cut apart with shears along alongitudinal top median line 7-7 Aandalong a corresponding median line on the underside of the v leg, by first having the patient lie on his back and thereafter on his face and then making the subsequent negative and positive plaster cast and rigid'or elastic orserniflexible or soft splints therefrom, as hereinabove :set forth. vThis will generally be done by not including .the entire `leg and 'foot in a `single splint. Also, in making the splint forthe leg,.it will of course.beunderstoodthat the ysame may be .made -when necessaryWithoutzrolling the 'patientover from one side to the other, by rst'rnakingthe'half'of the splint on the upper side of the leg with the patientlying on his back and thereafter proceeding asdescribedabove for making Vthe splint for the underside of the 'leg while Vthe leg is elevated sufficiently for this purpose.

Another'way of producing the splint for the leg, and in which'the splint can be used as an ambulatory cast, in which the cast or splint can be ywalkedon, would be as follows: Asfshown infFig. 16, the splint may bemade for a leg, which includes not `only the leg itself butalso the jfoot. This may be found desirable because ofthe extent `of the fracture or damage presentinlthe leg or owing tothe pathologicalcondition of the veins or tissnes. In making the splint in this way, the patient will preferably be lying on his ybackand the splint 78 of felt and monks cloth will be made as above described, but by enclosing both the leg and the foot. Then, the splint 78 `is cut with/the shears along a line 79y extending longitudinally along the side of the leg over the ankle, thenv forwardly around ythe foot to approximately the upper ends of the toes and thencerearwardly along the foot and longitudinally along the'other side of the leg, in a direction corresponding to the line 79, as shown ,in Fig. 16, Then the negative cast, positive cast andrigid or flexible or semi-'flexible or soft splints can be made therefrorn'in accordance with any of the procedures previously described. This'can be facilitatedby rolling the patient over from Ihis back to his face position or vice versa, when desired, or the operations can be conducted, instead, by lifting the leg from time to time, as above referred to.

In the case of varicose veins and similar pathological conditions in the leg or'elsewhere, splints may be advantageously made in the above manner and applied on theleg, for'instance as above referred to. However, a splint for this purpose may be made instead from a stockingof any desired fibrous material, which iis placed on the positive cast of the leg. Then the stockingis painted all over with latex, which is allowed to dry for two or three hours. After this, a razor blade is used to cut down the two sides of the cast longitudinally, followed by'taking ot carefully the two sections of the stocking with the set latex therein. These two halves are then put together by fastening zippers to'the longitudinal edges on both sides of the splint, or by means of fastenings made with hook-eyelets, as above referred to, or even with snap fasteners. The splint thus made can'beapplied to and taken off the leg in halves repeatedly at intervals for treatment of the leg, ventilation, washing, etc.

Also, as another example of a member or portion of the body for which the splints may be made, in case of a broken neck or paralysis or weakness of the neck muscles which require assistance, splints therefor may be made in a similar manner.

Accordingly, in making a neck splint the neck 80 is wrapped around under the chin carefully and softly with the impregnated felt strips 2, with or without overlying strips 0f monks cloth, Hanging out, as shown inFi'g. 1.7, until 'they overlie the shoulders of the patient, following the technique described vin connection vwith Figs. l and 2. Thereupon, with the shears, cuts 81 and 82 are made along the tops of the shoulders laterally of the patient. Then the patient is placed on his back and a fronthalf 83 is lifted off and, following the technique described in connection with Figs. l and 2, a plaster half of a negative cast is made in the place of the half 83 which has been removed. After this, the patient Ais -turned on his face and a back half 84 is- `able to be brought about during convalescence.

removed and a back half of the negative plaster cast is made in the place thereof, again following said technique of Figs. 1 and 2. The patient is put on his back again and the half of the felt splint 83 is restored in place of the plaster negative half and thereafter the same procedure is followed by turning the patient on his face and applying the rear felt half splint in place of the rear negative cast. After this, the two negative plaster halves are fastened together by windings of tape, the narrow or neck end of the resulting negative is closed with a dam of thick plaster of Paris and water mixture, and after coating the inside of the negative with silicate of soda solution in water, a positive plaster cast is made by pouring a thin mixture of plaster of Paris and water into the negative cast. When this positive cast has set it is removed and can be used for making thereon any of the previously described rigid or semi-rigid, elastic or semi-flexible, or soft splints to be placed around the neck of the patient and removed as often as necessary so as to facilitate the treatment, recovery and convalescence of the patient. In this way, 'the muscles of the neck can be restored gradually and completely to their original functions, as the supporting splints, especially when applied to the neck in the form of splints of increasing thinness and exibility and decreasing rigidity, can eifectively aid the restoring of the original strength and functions of the muscles of the neck and shoulders.

As shown in Fig. 18, I may provide a semi-flexible very light splint for nal convalescence, for any member of the body, for example the arm, which is made over the positive cast thereof. This splint is made of three thin layers of 37?;2 thick felt in six halves or pieces 85, 86, 87, 88, 89 and 90, so that the pieces 88, 89 and 90 overlap the lower sides of the pieces 85, 86 and 87, instead of the free lower edges previously referred to, but having open upper edges ending in flanges 91, 92, 93, 94, 95 and 96, provided with transverse holes 97 and 98 for eyelets and lacings. Series of lines of transverse Ventilating holes 99, 100 and 101, arranged longitudinally of the splint 102 thus produced, may be provided, if desired. This splint may be made of the three felt layers above referred to, secured together by any of the above techniques. However, for this purpose, thickened latex may rst be applied to the positive cast, after which each of the felt layers 85, 88, 86, 89, 87 and 90 is applied thereto in succession after having dipped it in thickened latex and wringing it out. After these felt layers are applied, they can be allowed to dry for about twelve hours, and are then brushed with a power-driven rotary brush to remove any loose nap.

Also, if desired, any of the final splints hereinabove described, if they are to be worn for a long time, can be covered with leather, such as a soft kid, by applying the same, according to the leather technique of my Patent No. 2,493,310, granted January 3, 1950, in pieces or halves corresponding in shape and size to the pieces of fabric that have already' been incorporated in the particular splint.

The modulating healing effect of the splints during the recovery of the patient will be found to be especially advantageous in the treatment of polio, in which the maximum possible activity or use of the muscles is desir- In other Words, the decrease of the degree of support with the increasing recovery of the patient is of paramount importance. I

Many other parts of the body can be provided with splints in this manner, as for example, the hips, shoulders, etc.

While I have described my invention above in detail I wish it to be understood that many changes may be made therein Without departing from the spirit of the same as defined in the claims.

I claim;

1. The process of making splints having a permanent impression of a body member therein which comprises the steps of applying fabric material impregnated with liquid rubber latex in uncured form to a body member to form a soft yielding fabric cast which readily conforms to change in the Ishape of the body member While the liquid rubber latex cures, maintaining the cast on the body member until the uncured liquid rubber latex is cured to the extent that a permanent impression of the body member is formed therein, cutting said fabric cast longitudinally into two separable portions, removing one of said portions, forming a first partial negative pl-aster of Paris cast on the body member in place of said removed portion while the body member is supported in the second portion of said fabric cast which serves as a lock that tends to prevent distortion of the fleshy portion of the body member while the partial negative plaster of Paris c-ast is being formed on said body member, removing the second portion of the fabric cast, forming a second partial uegative plaster of Paris cast on the body member in pla-ce of the removed portion of the fabric cast to form a complete negative plaster `of Paris cast on the body member, removing said negative plaster cast, forming a. positive plaster of Paris cast in said negative plaster cast, removing the positive plaster cast from the negative cast and then molding a negative cast of plastic and fabric material on said positive plaster cast to form a splint which contains' a permanent impression of lthe body member therein adapted to fit the contours of the bodyv member.

2. The process specified in claim l which includes the steps of cutting the fabric cast into a plurality of separable portions, removing consecutive portions of said fabric cast and forming in succession a substitute negative plaster of Paris cast on the body member in place thereof. i

3. The process specied in claim 1 which includes the step of supporting the body member in said rst partial plaster of Paris cast while the second plaster of Paris cast is being formed on said body member.

4. The process described in claim l which includes the step of dusting the liquid rubber latex with plaster of Paris to accelerate the setting and curing of the rubber latex.

References Cited in the file of this patent UNITED STATES PATENTS 101,743 King Apr. 12, 1870 224,784 Johnstone Feb. 24, 1880 631,205 Edgar Aug. 15, 1899 1,902,627 Elbogen Mar. 2l, 1933 2,082,599 Sawyer lune l, 1937 2,103,942 Gillin Dec. 28, 1937 2,292,531 Lovell Aug. 11, 1942 2,384,804 Anderson Sept. 18, 1945 2,512,081 Young June 20, 1950 2,812,570 Petersilie et al. Nov. 12, 1957 

